Astronomer Dr Meghan Gray on leap years and Julian dates. More links & stuff in full description below ↓↓↓ Meghan is making a "guest appearance" on Numberphile and is more familiar...
========== Our calendar is just a mess.It's a very complicated mismatch
of different cyclesand different lengths of time.And every once in a while, we
have to make an adjustment tothose lengths of time to
make things match.And one way we do that is every
once in a while addingan extra day to our calendar.And that extra day
is February 29.When we have an extra day, we
call that year a leap year.So there are two fundamental
units of time that we use thatare tied to actual,
physical events.One is the day, and that's the
time it takes for the Earth tomake one rotation
around its axis.The other is the year, and
that's the time it takes theEarth to make one revolution in
its orbit around the Sun.Every other unit we use-- the
week, the second, the hour--is fairly arb...
